Material is being squished according to the dimensions of object, how can I fix this?
You will automatically have this deformation with the Texture Coordinate Generated outlet, because it will try to fit the faces of your object. So you have several solutions:


Put a Vector > Mapping node between the Texture Coordinate and the Image Texture and play with the Z scale to find the correct value.
Use the Object outlet instead of the Generated one, it won't deform your texture. Anyway, you'll probably need a Vector > Mapping node between the Texture Coordinate and the Image Texture to scale up or down the texture.
Unwrap your object and open the UV/Image Editor to place the texture on your wall, but I guess it's a solution you try to avoid? It will be necessary if you want to be precise though.